Mario Giordana (born 16 January 1942) is an Italian prelate of the Roman Catholic Church who worked in the diplomatic service of the Holy See from 1976 to 2017.

He entered the diplomatic service of the Holy See on 8 March 1976 and fulfilled assignments in Indonesia, in the offices of the Secretariat of State, in Switzerland, France, Austria and Italy.

[1] On 27 April 2004, Pope John Paul II appointed him Titular Archbishop of Minora and Apostolic Nuncio to Haiti.

[1] He received his episcopal consecration in the Cathedral of Saluzzo on 29 May from Cardinal Angelo Sodano, Secretary of State.

[4] On 4 October 2017, Pope Francis appointed him a member of the Congregation for the Evangelization of Peoples[5] and on 15 December 2018 a member of the Congregation for the Causes of Saints[6] On 29 June 2020, Pope Francis appointed him Extraordinary Commissioner for the Fabric of Saint Peter to lead a commission to reform its administration.